1ARGZ_ADD(3) Linux Programmer's Manual ARGZ_ADD(3)
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6 argz_add, argz_add_sep, argz_append, argz_count, argz_create, argz_cre‐
7 ate_sep, argz_delete, argz_extract, argz_insert, argz_next, argz_re‐
8 place, argz_stringify - functions to handle an argz list
9
11 #include <argz.h>
12 error_t argz_add(char **argz, size_t *argz_len, const char *str);
14 error_t argz_add_sep(char **argz, size_t *argz_len,
16 const char *str, int delim);
17 error_t argz_append(char **argz, size_t *argz_len,
19 const char *buf, size_t buf_len);
20 size_t argz_count(const char *argz, size_t argz_len);
22 error_t argz_create(char * const argv[], char **argz,
24 size_t *argz_len);
25 error_t argz_create_sep(const char *str, int sep, char **argz,
27 size_t *argz_len);
28 void argz_delete(char **argz, size_t *argz_len, char *entry);
30 void argz_extract(const char *argz, size_t argz_len, char **argv);
32 error_t argz_insert(char **argz, size_t *argz_len, char *before,
34 const char *entry);
35 char *argz_next(const char *argz, size_t argz_len, const char *entry);
37 error_t argz_replace(char **argz, size_t *argz_len, const char *str,
39 const char *with, unsigned int *replace_count);
40 void argz_stringify(char *argz, size_t len, int sep);
42
44 These functions are glibc-specific.
45 An argz vector is a pointer to a character buffer together with a
47 length. The intended interpretation of the character buffer is an ar‐
48 ray of strings, where the strings are separated by null bytes ('\0').
49 If the length is nonzero, the last byte of the buffer must be a null
50 byte.
51 These functions are for handling argz vectors. The pair (NULL,0) is an
53 argz vector, and, conversely, argz vectors of length 0 must have null
54 pointer. Allocation of nonempty argz vectors is done using malloc(3),
55 so that free(3) can be used to dispose of them again.
56 argz_add() adds the string str at the end of the array *argz, and up‐
58 dates *argz and *argz_len.
59 argz_add_sep() is similar, but splits the string str into substrings
61 separated by the delimiter delim. For example, one might use this on a
62 UNIX search path with delimiter ':'.
63 argz_append() appends the argz vector (buf, buf_len) after
65 (*argz, *argz_len) and updates *argz and *argz_len. (Thus, *argz_len
66 will be increased by buf_len.)
67 argz_count() counts the number of strings, that is, the number of null
69 bytes ('\0'), in (argz, argz_len).
70 argz_create() converts a UNIX-style argument vector argv, terminated by
72 (char *) 0, into an argz vector (*argz, *argz_len).
73 argz_create_sep() converts the null-terminated string str into an argz
75 vector (*argz, *argz_len) by breaking it up at every occurrence of the
76 separator sep.
77 argz_delete() removes the substring pointed to by entry from the argz
79 vector (*argz, *argz_len) and updates *argz and *argz_len.
80 argz_extract() is the opposite of argz_create(). It takes the argz
82 vector (argz, argz_len) and fills the array starting at argv with
83 pointers to the substrings, and a final NULL, making a UNIX-style argv
84 vector. The array argv must have room for argz_count(argz, argz_len) +
85 1 pointers.
86 argz_insert() is the opposite of argz_delete(). It inserts the argu‐
88 ment entry at position before into the argz vector (*argz, *argz_len)
89 and updates *argz and *argz_len. If before is NULL, then entry will
90 inserted at the end.
91 argz_next() is a function to step through the argz vector. If entry is
93 NULL, the first entry is returned. Otherwise, the entry following is
94 returned. It returns NULL if there is no following entry.
95 argz_replace() replaces each occurrence of str with with, reallocating
97 argz as necessary. If replace_count is non-NULL, *replace_count will
98 be incremented by the number of replacements.
99 argz_stringify() is the opposite of argz_create_sep(). It transforms
101 the argz vector into a normal string by replacing all null bytes ('\0')
102 except the last by sep.
103
105 All argz functions that do memory allocation have a return type of er‐
106 ror_t (an integer type), and return 0 for success, and ENOMEM if an al‐
107 location error occurs.
108
110 For an explanation of the terms used in this section, see at‐
111 tributes(7).
112 ┌──────────────────────────────────┬───────────────┬─────────┐
114 │Interface │ Attribute │ Value │
115 ├──────────────────────────────────┼───────────────┼─────────┤
116 │argz_add(), argz_add_sep(), │ Thread safety │ MT-Safe │
117 │argz_append(), argz_count(), │ │ │
118 │argz_create(), argz_create_sep(), │ │ │
119 │argz_delete(), argz_extract(), │ │ │
120 │argz_insert(), argz_next(), │ │ │
121 │argz_replace(), argz_stringify() │ │ │
122 └──────────────────────────────────┴───────────────┴─────────┘
123
125 These functions are a GNU extension.
126
128 Argz vectors without a terminating null byte may lead to Segmentation
129 Faults.
130
132 envz_add(3)
133
135 This page is part of release 5.10 of the Linux man-pages project. A
136 description of the project, information about reporting bugs, and the
137 latest version of this page, can be found at
138 https://www.kernel.org/doc/man-pages/.
139 2020-11-01 ARGZ_ADD(3)